The broad, long-term objective of this study is to determine the most effective imaging procedures required to stage and monitor head and neck (H&N) carcinomas. The specific aims of these projects are: 1) To determine which imaging method (CT, MR, or ultrasonography) is the most accurate for staging of the primary tumor. 2) To determine the relative sensitivities and specificities of CT, MR, and ultrasonography in the detection and staging of malignant nodal disease of the head & neck. 3) To determine if imaging studies are accurate in predicting: a) the immediate operability of the tumor by evaluating local extension of the primary tumor, with particular emphasis on invasion of the neck vessels, as well as, skull base & foramina, bony & cartilaginous structures, and tongue. b) the long-term response to radiation and/or chemotherapy in non-surgical cases, c) the local regional control and d) survival. 4) To evaluate the sensitivity and specificity of each imaging modality in detection of recurrent disease during sequential follow-up. 5) To use Receiver-Operating Characteristic (ROC) curves to compare CT alone, MR alone, ultrasonography alone, and CT, MR and US jointly in the staging and in the monitoring of the primary tumor, as well as nodal disease. 6) To participate in the development of protocols, mechanisms and analytic approaches which will be appropriate for collaborative imaging studies and, eventually, for the costefficient imaging of head & neck tumor patients. The health-relatedness of the project rests in the determination the most cost effective imaging approach for the accurate staging and follow-up in these patients. The experimental design and methodology would employ expertise from experienced radiologists, H&N surgeons, radiation oncologists and pathologists evaluating about 75 new patients per year. After the initial clinical examination, the patient is referred for the imaging diagnostic studies, including contrast enhanced CT, MRI , and an US exam of the head & neck. A multimodality H&N tumor board will stage the lesion and decide on appropriate therapy. If surgically resected, the primary tumor would have frozen section, and inked margins. Followup of the patient will include repeat imaging at designated 3 month intervals or if clinical recurrence was detected. Correlation of the sensitivity and specificity of each modality would be assessed for tumor recurrence vs scar or inflammation. ROC curves will be generated and will be used to determine the relative sensitivities and specificities of each imaging modality for determining the presence, depth of tumor invasion, and extent of regional spread.